---
creation_epoch: 1760400126
lastmod_epoch: 1760400126
categories: ['Tech Tricks
title: Attempting Firmware Access to Calix GigaSpire Blast GS4220E
---
I was unsuccessful at getting a TTL Serial USB UART to show the console during boot. It may be disabled or the PINs may be for JTAG instead. I did get a working GND + VCC (3.3V).
Removal of the bottom required 3 screws (under the rubber feet) and pushing some plastic clips in. I was able to do so without any plastic clips breaking.
Useful FCC document: https://fccid.io/2ABLK-GS4227/Internal-Photos/Internal-photos-5245853.pdf
Some photos of the process:
